void setZeroes(vector<vector<int> > &matrix) {
if(matrix.empty() || matrix[0].empty()) return;
int m = matrix.size(), n = matrix[0].size();
// find if the 1st row/col needs to be set as zero
bool isFirstRowZero = false;
bool isFirstColZero = false;
for(int j=0; j<n; j++) {
if(matrix[0][j]==0) {
isFirstRowZero = true;
break;
}
}
for(int i=0; i<m; i++) {
if(matrix[i][0]==0) {
isFirstColZero = true;
break;
}
}
// use 1st row/col to record whether to set each col/row as zero
for(int i=1; i<m; i++) {
for(int j=1; j<n; j++) {
if(matrix[i][j]==0) {
matrix[i][0] = matrix[0][j] = 0;
}
}
}
// set rows & cols
for(int i=1; i<m; i++) {
if(matrix[i][0]==0) setRowCol(matrix, i, true);
}
for(int j=1; j<n; j++) {
if(matrix[0][j]==0) setRowCol(matrix, j, false);
}
// set first row & col
if(isFirstRowZero) setRowCol(matrix, 0, true);
if(isFirstColZero) setRowCol(matrix, 0, false);
}
void setDim(int d) { setRowCol(d, 1); }
Mvector(const Mmatrix &o):Mmatrix(o) {
setRowCol(o.getRow() * o.getCol(), 1);
}
